Integrated lead suspension and method of construction

ABSTRACT

An integrated lead suspension includes a solder ball that is placed between a lead wiring pad provided on a flexure of the suspension, and a bonding pad provided on a slider of a head gimbal section. The lead wiring pad and bonding pad are soldered by melting the solder ball. As a result, there is provided a recessed section into which a solder ball is placed by way of surface raised sections, using gravitational force, in the vicinity of the center line of the surface of the lead wiring pad. In this way the position of the solder ball is not displaced from the center line when a bonding pad and lead wiring pad are connected by means of a solder ball.

RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 10/459,343, filed Jun. 11, 2003, now U.S. Pat. No. 6,879,465,entitled “Integrated Lead Suspension and Method of Construction”.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to an integrated lead suspension thatsupports a magnetic head gimbal section of a hard disk drive, and moreparticularly to an integrated lead suspension that can improve problemsthat arise when a lead wiring pad provided on a flexure section of thesuspension and a bonding pad provided on a slider of a head gimbalsection of the suspension are joined.

2. Description of the Related Art

As hard disk drives have become smaller in recent years, the design andconstruction of the various parts of the suspension that moves themagnetic head have become more difficult, and, in particular, the taskof connecting leads to the slider that holds the magnetic head hasbecome extremely difficult. Moreover, the weight, wiring positions, andso forth, of the leads themselves have come to affect head control, andconsequently integrated lead suspensions have come to be known in whichvariations due to wiring are suppressed by bonding a wiring section, orforming a wiring pattern, on the suspension.

With an integrated lead suspension, it is necessary to join together alead wiring pad provided on the flexure section on the suspension sideand a bonding pad provided on the slider, but the two connectingsurfaces have a positional relationship such that the extended planes ofthe two pads are orthogonal (when the two planes are viewed from theside, a virtual right angle is formed at the point of intersection), andtherefore the technology for connecting normal opposing planes cannothandle this case, and various new technologies are used.

For example, one known method for joining a lead wiring pad and bondingpad that have an orthogonal positional relationship is apple bonding,using a gold (Au) ball. With apple bonding, a gold ball is pushed intothe virtual right angle formed by the above-described two pads, andconnection is made by means of ultrasonic welding. An example of anothermethod is a method using a solder ball for which application has beenmade by the present applicants in Japanese Patent Application No.2000-189148 or Japanese Patent Application No. 2001-039888.

With a method using a solder ball, the integrated lead suspension issupported so that the virtual right angle formed by the above-describedtwo pads faces upward vertically, and a solder ball is placed betweenthe two pads. Following this, the solder is melted by irradiating thesolder ball with a laser beam, connecting the two pads.

FIG. 15 is a drawing showing the case where the lead wiring pad andbonding pad are joined using a solder ball in a conventional integratedlead suspension. A suspension flexure 5 has a 2-layer constructioncomprising a polyimide layer 17, which is insulating polymeric material,and a stainless steel foil layer 18. A lead 10, which is a conductivelayer, is further formed on the polyimide layer 17, and at the end ofthe lead 10 is formed a lead wiring pad 12 that is wider than the lead10 so as to be of sufficient area for solder connection.

The shape of the polyimide layer 17 and stainless steel foil layer 18can be processed by performing etching, for example, after coating thenecessary parts with a resist. Also, when the polyimide layer 17 is aphotosensitive polyimide layer, the shape can be processed by performingexposure and development after coating the necessary parts of thepolyimide layer 17 with a resist or the like.

An aperture section 11 is formed in the tip section of the lead wiringpad 12 on the flexure 5 in order to prevent such problems as overflow ofadhesive adhering to the lead wiring pad 12 when the slider is bonded tothe suspension, or the polymeric polyimide layer 17 being altered byheat emission due to laser beam radiation. Therefore, the tip section ofthe lead wiring pad 12 comprises in-air wiring that projects into theaperture section 11.

A slider 6 that incorporates a magnetic head for a hard disk is attachedto the flexure 5, and a bonding pad 15 of the slider 6 is placed in aposition orthogonal to the lead wiring pad 12 as described above. Thus,the virtual orthogonal axes at which the plane extended from the planeof the bonding pad 15 intersects the plane extended from the plane ofthe lead wiring pad 12 form an angle of 90 degrees (a right angle).

When the bonding pad 15 and lead wiring pad 12 are connected with asolder ball, the suspension (flexure 5) is fixed in the direction inwhich the virtual right angle formed by the bonding pad 15 and leadwiring pad 12 opens upward in a vertical direction. Normally, theflexure 5 is fixed so that the lead wiring pad 12 on the flexure 5 andthe bonding pad 15 on the slider 6 both form an angle 45 degrees abovethe horizontal while both maintaining a state in which the positionalrelationship of the two is orthogonal. Then a solder ball 400 is droppedfrom a solder ball transfer apparatus (not shown) between the two fixedpads. The two pads are then connected by melting the solder ball 400 byheating it by means of a laser beam radiation apparatus or the like (notshown).

With a conventional integrated lead suspension, the bonding pad 15 andlead wiring pad 12 are connected by means of a solder ball in this way.Integral-type wiring suspensions are classified into the three typesbelow according to differences in their construction methods. In theconstruction of all three types, connection is performed as describedabove when the bonding pad 15 and lead wiring pad 12 are connected bymeans of a solder ball.

(a) An additive type in which copper foil wiring and pads are additivelyformed on insulating material of the suspension

(b) A subtractive type in which wiring and pads are formed by beingetched from copper foil formed as a sheet on insulating material of thesuspension

(c) An FPC type in which a flexible substrate (FPC) on which copper foilwiring and pads are formed is bonded to the suspension

However, with a conventional integrated lead suspension, when thebonding pad 15 and lead wiring pad 12 are connected by means of a solderball there is problem in that, since the solder ball is almost sphericaland the surfaces of the bonding pad 15 and lead wiring pad 12 are almostflat, the solder ball rolls in the virtual right-angle axis direction(direction A or direction B in FIG. 15) at which the extended planes ofthe two pads are orthogonal, and the position of the solder ball isdisplaced from the center line CL of each pad shown in FIG. 15. Thisproblem arises in a similar way with all the above-described types.

Also, with the additive type, in particular, die wear occurs wherebyareas near the edge take on an inclined beveled shape as shown in 12 athrough 12 c in FIG. 15, as a result of which the area of the flatsection 12 d diminishes, and moreover, the surface of remaining flatsection 12 d is rough and has undulations. Consequently, the additivetype is more susceptible than the other types to the problem ofdisplacement of the position of the solder ball from the center line CL.

If the position of the solder ball is displaced from the center line,when the two pads are connected by melting the solder ball with laserbeam radiation, there arises a solderless state in which there is nosolder ball in the connecting region, or a solder connection defectbecause the solder ball, although in the connecting region, is displacedfrom the center line. Solder connection defects may include, in the casewhere solder does not connect both pads, partial soldering in which onlyparts of the two pads are imperfectly soldered, or a bridge connectionthat connects adjacent pads of the same kind.

The present invention has been devised in order to solve suchconventional problems as described above, and has as its object theprovision of an integrated lead suspension whereby, when a bonding padand lead wiring pad are connected by means of a solder ball, theposition of the solder ball is not displaced from the center line.

SUMMARY OF THE INVENTION

In order to achieve the above-described object, an integrated leadsuspension of the present invention comprises a lead wiring pad providedon the flexure section of the suspension, a bonding pad provided on theslider of the head gimbal section of the suspension, and a solder ballthat is placed between the lead wiring pad and the bonding pad, so thatthe lead wiring pad and bonding pad are soldered by melting the solderball; and a recessed section is provided into which the solder ball isdropped from the surface of the lead wiring pad, using the force ofgravity, in the vicinity of the center line of the surface of the leadwiring pad.

The recessed section of an integrated lead suspension of the presentinvention may be configured so that a difference in level, a curvedsurface, or an inclined surface is formed between the part into whichthe solder ball is dropped and the portions on both sides thereof.

The recessed section of an integrated lead suspension of the presentinvention may be configured so that the distances from the center lineof the part into which the solder ball is dropped to the portions onboth sides thereof are equal.

The recessed section of an integrated lead suspension of the presentinvention may have the part into which the solder ball is dropped thathas a groove shape parallel to the center line or a notched section.

The recessed section of an integrated lead suspension of the presentinvention may have the part into which the solder ball is dropped thathas a U-shape with the opening side facing downward and the portions onboth sides thereof parallel to the center line, or a V-shape with theopening side facing downward and the portions on both sides thereofextending from the apex positioned on the center line toward the openingside.

A construction method of an integrated lead suspension of the presentinvention comprises providing a lead wiring pad on a flexure section ofthe suspension, providing a bonding pad on a slider of a head gimbalsection of the suspension, and placing a solder ball between the leadwiring pad and the bonding pad, so that the solder ball is melted tosolder the lead wiring pad and bonding pad together, and when a leadwiring pad is formed using etching technology, a recessed section issimultaneously formed into which a solder ball is dropped from thesurface of the lead wiring pad, using the force of gravity, in thevicinity of the center line of the surface of that lead wiring pad.

A construction method of an integrated lead suspension of the presentinvention may comprise providing a lead wiring pad a flexure section ofthe suspension, providing a bonding pad on a slider of a head gimbalsection of the suspension, and placing a solder ball between the leadwiring pad and the bonding pad, so that the solder ball is melted tosolder the lead wiring pad and bonding pad together wherein theconstruction method may comprise the steps of: first forming a leadwiring pad having a flat surface, and thereafter providing a recessedsection into which a solder ball is dropped from the surface of the leadwiring pad, using the force of gravity, in the vicinity of the centerline of the surface of the lead wiring pad.

A construction method of an integrated lead suspension of the presentinvention may provide a recessed section using etching technology,bending, or die press working.

When an integrated lead suspension of the present invention is ofadditive type, the construction method may comprise the steps of: firstforming a lead wiring pad having a flat surface using copper platingtechnology, and thereafter causing protrusion by plating additionalcopper on the portions on both sides thereof excluding the vicinity ofthe center line of the surface of the lead wiring pad and providing arelatively recessed section.

When an integrated lead suspension of the present invention is ofadditive type, the construction method may comprise the steps of: firstforming an underlying recessed section using etching technology on anunderlying layer of the lead wiring pad, and thereafter forming arecessed section by forming a lead wiring pad using copper platingtechnology on that underlying layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an oblique drawing showing the overall configuration of anintegrated lead suspension according to Embodiment 1 of the presentinvention;

FIG. 2 is an expanded partial drawing of the tip section on which aslider is located in the integrated lead suspension shown in FIG. 1;

FIG. 3 is a cross-sectional drawing showing a solder ball joiningapparatus that connects two pads by irradiating a solder ball placedbetween the two pads with a laser beam;

FIG. 4 is a cross-sectional drawing showing an enlarged view of thestate where a solder ball is positioned at the tip section of anintegrated lead suspension supported by the work jig shown in FIG. 3;

FIG. 5 is a cross-sectional drawing showing an enlarged view of thestate where the solder ball shown in FIG. 4 has melted and joined abonding pad and a lead wiring pad;

FIG. 6 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 1 of thepresent invention;

FIG. 7 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 2 of thepresent invention;

FIG. 8 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 3 of thepresent invention;

FIG. 9 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 4 of thepresent invention;

FIG. 10 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 5 of thepresent invention;

FIG. 11 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 6 of thepresent invention;

FIG. 12(A) is a drawing showing pads of the same kind as conventionallead wiring pads during the process of manufacture, and FIG. 12(B) is anoblique drawing showing an enlarged view of the main parts in anintegrated lead suspension according to Embodiment 7;

FIG. 13(A) is a drawing showing pad base sections formed by etching,etc., on a polyimide layer, which is insulating polymeric material,during the process of manufacture, and FIG. 13(B) is an oblique drawingshowing an enlarged view of the main parts in an integrated leadsuspension according to Embodiment 8;

FIG. 14(A) is a drawing showing pad base sections formed by etching,etc., on a polyimide layer, which is insulating polymeric material,during the process of manufacture, and FIG. 14(B) is an oblique drawingshowing an enlarged view of the main parts in an integrated leadsuspension according to Embodiment 9; and

FIG. 15 is a drawing showing the case where a lead wiring pad andbonding pad are joined using a solder ball in a conventional integratedlead suspension.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The present invention will now be described in detail based on theembodiments shown in the attached drawings.

FIG. 1 is an oblique drawing showing the overall configuration of anintegrated lead suspension according to Embodiment 1 of the presentinvention, and FIG. 2 is an expanded partial drawing of the tip sectionon which a slider is located in the integrated lead suspension shown inFIG. 1.

An integrated lead suspension 1 mainly comprises a base plate 2, loadbeam 4, suspension plate 3, and flexure 5. An aperture section 2 aformed in the base plate 2 is supported by suspension support means of ahard disk drive (not shown), and the integrated lead suspension 1rotates in the directions of arrows R, centered on the aperture section2 a.

The suspension plate 3 is bonded to the base plate 2, and the load beam4 is fixed to the suspension plate 3. The suspension plate 3 is flexiblysupported by the base plate 2, and the desired suspensioncharacteristics are obtained by means of the formed aperture section.The load beam 4 is extended in a direction radiating from the axis ofrotation about which the integrated lead suspension 1 rotates, and a tab7 is formed on its tip section.

The flexure 5 is a lead support mechanism that extends in a crank shapefrom the tip section of the integrated lead suspension 1 to amulti-connector section 9, and is laser-welded to the load beam 4 atthree places and is also fixed to the base plate 2. On the upper surfaceof this flexure 5 (the surface uppermost in FIG. 1), four leads 8 arearranged via an insulating sheet so as not to be in mutual contact. Theprincipal parts of these leads are protected by a protective sheet.

The vicinity of the tip section of the flexure 5 is fixed to the loadbeam 4, but the leads forward of that fixed part are free of the loadbeam 4, and here an arch-shaped aperture section is formed. The slider 6is bonded to a flexure tang 14 that is formed projecting toward thecenter of the arch-shaped aperture section from a platform 13 of themost forward part of the flexure 5.

As regards this flexure tang 14, a position at the center of the slider6 is supported by a pivot (not shown) projecting from the load beam 4.By this means, the slider 6 can maintain predetermined amounts ofinclination (called pitch, roll, and yaw) in all directions with respectto the load beam 4.

The four leads 8 shown in FIG. 1 are divided into pairs of leads 10 fromwhere they emerge from the protective sheet toward the most forward partas shown in FIG. 2, and arrive at the platform 13 after bending throughalmost a right angle, floating free, at the side of the aperture section11. On the platform 13, the leads 10 bend again through almost a rightangle toward four bonding pads 15 formed on the most forward side 6 a ofthe slider 6.

At the end of each bent lead 10 is formed a lead wiring pad 20 that isto be connected to a bonding pad 15 formed on the most forward side 6 aof the slider 6. An aperture section 11 is formed between the platform13 and flexure tang 14, which is the solder connection area for thebonding pads 15 and lead wiring pads 20.

Next, the method of connecting a bonding pad 15 and lead wiring pad 20using a solder ball will be described. In summary, the integrated leadsuspension 1 is first supported so that the right angle formed at theintersection of the surface (connecting surface) of a bonding pad 15 andthe surface (connecting surface) of a lead wiring pad 20 faces upward ina vertical direction, and then a solder ball is placed between the twopads, after which the two pads are connected by irradiating the solderball with a laser beam.

First, the method will be described below whereby the integrated leadsuspension 1 is supported so that the right-angle section formed by thesurface of a bonding pad 15 and the surface of a lead wiring pad 20faces upward in a vertical direction.

FIG. 3 is a cross-sectional drawing showing a solder ball joiningapparatus that connects the two pads by irradiating a solder ball placedbetween the two pads with a laser beam. This is a main configurationdrawing showing an approaching optical (laser) apparatus 200 that is toirradiate the solder ball 400 with a laser beam 201, a work jig 301 thatsupports the integrated lead suspension 1, and a mounting stand 300 thatsupports this work jig 301.

The mounting stand 300 has a mounting surface 300 a at a 45-degreeincline to the horizontal plane H, and the work jig 301 is placed onthis mounting surface 300 a so that it is also at a 45-degree incline tothe horizontal plane H. The slider 6 is placed on the work jig 301, andthe integrated lead suspension 1 is mounted with the slider 6 toward itsupper surface.

At this time, in the integrated lead suspension 1 supported by the workjig 301, the joining surfaces of the bonding pads at its tip section andthe joining surfaces of the opposing lead wiring pads are at practically45 degrees to the horizontal plane. In this way, the virtual right-anglesection formed by the surface of a bonding pad 15 and the surface of alead wiring pad 20 is supported so as to open toward the upper part ofthe vertical direction V on the work jig 301.

Next, a solder ball 400 is placed between the two pads, and then thesolder ball 400 is irradiated with a laser beam 201. As the method ofplacing the solder ball 400 between the two pads and performing laserbeam 201 radiation is disclosed in detail by the present applicants inJapanese Patent Application No. 2000-189148 and Japanese PatentApplication No. 2001-039888, and the method of placing the solder ball400, the configuration of the optical apparatus 200, and so forth, arenot-directly relevant to the present application, only a briefdescription thereof will be given here.

The optical apparatus 200 is a fiber laser termination module that usesan optical fiber in a resonator, has a series of optical lenses arrangedin an internal optical path, and forms an aerial laser beam path space.The optical lenses converge scattered light output from the opticalfiber, and output this as a laser beam 201 from the forward section ofthe optical apparatus 200.

FIG. 4 is a cross-sectional drawing showing an enlarged view of thestate where a solder ball is positioned at the tip section of theintegrated lead suspension 1 supported by the work jig 301 shown in FIG.3. A bonding pad 15 and lead wiring pad 20 are positioned so as to eachbe raised 45 degrees above the horizontal plane, the plane extended fromthe surface of the bonding pad 15 and the plane extended from thesurface of the lead wiring pad 20 are orthogonal, and a virtual rightangle is formed between the two pads. The virtual right angle openstoward the top of the vertical direction V, and is set to an anglesuitable for catching a solder ball 400 supplied from above.

When a solder ball 400 transported by means of suction pad is placed,and comes to rest, so as to touch the joining surfaces of the bondingpad 15 and lead wiring pad 20, the optical apparatus 200 is moved to theradiation position by means of moving means (not shown), and the solderball 400 is irradiated with a laser beam 201 converged to apredetermined spot diameter.

In the period from placement of this solder ball 400 until it isirradiated with the laser beam 201, a predetermined quantity of nitrogengas N₂ constituting an inert atmosphere is injected from a nitrogen gasentry pipe of the mounting stand 300 in order to suppress solderoxidation. By this means, the bonding pad 15, lead wiring pad 20, andsolder ball 400 are placed in an inert atmosphere. When nitrogen gas isinjected, the injection location and flow rate are considered to preventa change in the position of the stationary solder ball due to the gaspressure during injection, but even so, the solder ball may move due tothe injection of nitrogen gas if the surface condition of the pads ispoor, for example.

While this inert atmosphere is maintained, the optical apparatus 200emits a laser beam 201 and melts the solder ball 400 by heating it, soconnecting the bonding pad 15 and lead wiring pad 20. If the externaldiameter of the solder ball is around 120 mm, for example, the spotdiameter of the laser beam at this time is set to around 150 to 200 mm.

As a result of melting the solder in an inert atmosphere produced bynitrogen gas N₂ in this way, inert nitrogen gas N₂ coats the soldersurface when the solder cools and forms a joint after melting, thusenabling oxidation of the solder to be prevented.

FIG. 5 is a cross-sectional drawing showing an enlarged view of thestate where the solder ball shown in FIG. 4 has melted and joined thebonding pad 15 and lead wiring pad 20. The melted solder 401 spreadsupward on both the bonding pad 15 connecting surface and the lead wiringpad 20 connecting surface due to the wettability of the solder, andforms a shape that connects the two pads. The melted solder spreads tothe front surface at the top of both the bonding pad 15 connectingsurface and the lead wiring pad 20 connecting surface, and if the twoare connected in an inverted arch shape as shown in FIG. 5, a fillet 401showing a good connection state is formed. In order for a goodconnection state such as that shown in FIG. 5 to be achieved, the solderball 400 must be placed in the vicinity of the center line of the sidedirection (virtual right angle axis direction) on each pad.

FIG. 6 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension of this embodiment, and shows the areawhere a lead wiring pad and bonding pad are joined using a solder ball.The difference between the integrated lead suspension of this embodimentshown in FIG. 6 and the conventional integrated lead suspension shown inFIG. 15 lies only in the structure of the lead wiring pads 20. Otherwisethe configuration is the same as that of the conventional integratedlead suspension shown in FIG. 15.

With a lead wiring pad 20 of this embodiment, the same kind of pad as aconventional lead wiring pad shown in FIG. 15 is first formed, and thenetching is further performed on its surface. A pad of the same kind as aconventional lead wiring pad is formed, in the case of a subtractivetype or FPC type integrated lead suspension, by coating areas requiringa Cu (copper) foil layer with a resist, etching other parts, and thenremoving the resist; and in the case of an additive type integrated leadsuspension, by setting a seed layer on a polyimide layer 17 by means ofsputtering, performing Cu (copper) plating after coating unnecessaryareas thereupon with a resist, and then removing the resist. In thisembodiment, following this, half-etching is performed after coatingraised section 22 and raised section 23 with another resist, and therecessed groove section (recessed section) 21 shown in FIG. 6 isprovided on the lead wiring pads 20.

As a result, a recessed groove section 21 is formed by half-etchingalong the center line CL in a lead wiring pad 20 of this embodiment, andunetched raised section 22 and raised section 23 remain on either sideof the recessed groove section 21, so that a difference in level isprovided between the recessed groove section 21 and raised section 22and between the recessed groove section 21 and raised section 23.

This difference in level need not be a sharply-defined difference inlevel as shown in FIG. 6, but, for example, may be configured so thatthe recessed groove section 21 sinks gently below raised section 22 andraised section 23 on a curved surface, or may be configured so that therecessed groove section 21 sinks gently below raised section 22 andraised section 23 on an inclined surface.

Due to the formation of this difference in level, a solder ball 400 isdropped into the recessed groove section 21—that is, between raisedsection 22 and raised section 23—under the force of gravity, and istemporarily fixed so that the center of the solder ball 400substantially coincides with the center line CL on the recessed groovesection 21 and does not move in the virtual right angle axis directionbetween the two pads. As a result, the solder ball 400 will no longermove even if subjected to some kind of stress in the virtual right angleaxis direction (direction A or direction B shown in FIG. 6) due to thesubsequent injection of nitrogen gas, etc., or vibration when theoptical apparatus 200 moves, for example.

As the dimensions of the recessed groove section 21, if, for example,the width of a lead wiring pad 20 is 148 mm and the diameter of thesolder ball is 120 mm, a width (74 mm) of half the width of a leadwiring pad 20 and a thickness of half the thickness of a lead wiring pad20 are appropriate.

In this embodiment, a difference in level is provided between a recessedgroove section 21 in the vicinity of the center line CL and theperipheral areas by etching on a lead wiring pad 20, but the recessedgroove section 21 may also be formed not by providing a difference inlevel with respect to peripheral areas by etching, but, for example, bysinking the vicinity of the center line CL gently on a curved surfacethat continues from the peripheral areas, or by sinking the vicinity ofthe center line CL on an incline from the peripheral areas toward thevicinity of the center line CL.

In this embodiment, a recessed groove section 21 is formed usinghalf-etching around the center line CL of a lead wiring pad 20, butanother shape may also be formed by etching, as long as it is a shapethat allows a solder ball 400 to be dropped into it by force of gravity.For example, an oval or circular recessed section, or a rhomboidal orrectangular recessed section, may be provided in the vicinity of thecenter of a lead wiring pad 20 by etching.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a recessed groove section 21 in a lead wiring pad 20 bymeans of half-etching, the center of a solder ball 400 substantiallycoincides with the center line CL of the lead wiring pad 20, and istemporarily fixed so that it does not move in the virtual right angleaxis direction between the two pads, as a result of which the solderball 400 will no longer move in the right angle axis direction even ifsubjected to some kind of stress in the virtual right angle axisdirection due to subsequent injection of an inert gas or movement of theoptical apparatus 200, for example, thereby enabling the good solderconnection state shown in FIG. 5 to be achieved.

FIG. 7 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 2 of thepresent invention. The only difference between this embodiment andEmbodiment 1 is that the shape of the lead wiring pads 30 is different.Otherwise the configuration is the same as that of the integrated leadsuspension according to Embodiment 1 shown in FIGS. 1-6.

A lead wiring pad 30 of this embodiment is formed, in the case of asubtractive type or FPC type integrated lead suspension, by coatingareas requiring a Cu (copper) foil layer with a resist, etching otherparts, and then removing the resist; and in the case of an additive typeintegrated lead suspension, by setting a seed layer on a polyimide layerby means of sputtering, performing Cu (copper) plating after coatingunnecessary areas thereupon with a resist, and then removing the resist.At this time, the U-shaped notched section (recessed section) 31 shownin FIG. 7 is formed in each lead wiring pad 30 by changing the resist.

The U-shaped notched section 31 is formed so that the straight-lineparts of a U with the aperture facing downward are parallel to thecenter line CL. On either side of the U-shaped notched section 31 a forksection (raised section) 32 and fork section (raised section) 33 areformed, and a space parallel to the center line CL is formed by theU-shaped notched section 31 between fork section 32 and fork section 33.

Due to the formation of this space by the U-shaped notched section 31, asolder ball 400 is dropped into the U-shaped notched section 31—that is,between fork section 32 and fork section 33—under the force of gravity,and is temporarily fixed so that the center of the solder ball 400substantially coincides with the center line CL on the U-shaped notchedsection 31 and does not move in the virtual right angle axis directionbetween the two pads. As a result, the solder ball 400 will no longermove even if subjected to some kind of stress in the virtual right angleaxis direction (direction A or direction B shown in FIG. 7) due to thesubsequent injection of nitrogen gas, etc., or vibration when theoptical apparatus 200 moves, for example.

As the width of the section parallel to the center line CL in theU-shaped notched section 31, if, for example, the width of a lead wiringpad 30 is 148 mm and the diameter of the solder ball is 120 mm, a widthof half (74 mm) or ⅓ (approx. 49 mm) the width of a lead wiring pad 30is appropriate. As for the curved section of the U-shaped notchedsection 31, any arc-shaped curve can be used that enables the parallelsections on either side to be connected.

In this embodiment, a U-shaped notched section 31 is formed peripheralto the center line CL of a lead wiring pad 30, but a different shape mayalso be formed as long as it is a shape that enables a solder ball 400to be dropped into it under the force of gravity. For example, an ovalor circular notched section may be provided in the vicinity of thecenter of a lead wiring pad 30.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a U-shaped notched section 31 in a lead wiring pad 30, inthe same way as in above-described Embodiment 1, the center of a solderball 400 substantially coincides with the center line CL of the leadwiring pad 30, and is temporarily fixed so that it does not move in thevirtual right angle axis direction between the two pads, as a result ofwhich the solder ball 400 will no longer move in the right angle axisdirection even if subjected to some kind of stress in the virtual rightangle axis direction due to subsequent injection of an inert gas ormovement of the optical apparatus 200, for example, thereby enabling thegood solder connection state shown in FIG. 5 to be achieved.

FIG. 8 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 3 of thepresent invention. The only difference between this embodiment andEmbodiment 2 is that the shape of the lead wiring pads 40 is different.Otherwise the configuration is the same as that of the integrated leadsuspension according to Embodiment 2 shown in FIG. 7.

As the method of forming a lead wiring pad 40 of this embodiment, in thesame way as in the Embodiment 2, in the case of a subtractive type orFPC type integrated lead suspension, the pad is formed by etching partsnot coated with a resist, and in the case of an additive type integratedlead suspension, by performing Cu (copper) plating of parts not coatedwith a resist. At this time, the V-shaped notched section (recessedsection) 41 shown in FIG. 8 is formed in each lead wiring pad 40 bychanging the resist.

The V-shaped notched section 41 is formed so that the aperture of a Vwith the opening side facing downward is at the tip of the lead wiringpad 40, and a straight line from the apex of the V through the midpointof the two sides of the aperture of the V coincides with the center lineCL. On either side extending from the apex of the V of the V-shapednotched section 41 toward the aperture of the V, a fork section (raisedsection) 42 and fork section (raised section) 43 are formed, and a spacethat gradually widens as it approaches the connecting area is formed bythe V-shaped notched section 31 between fork section 42 and fork section43.

Due to the formation of this space by the V-shaped notched section 41, asolder ball 400 is dropped into the V-shaped notched section 41—that is,between fork section 42 and fork section 43—under the force of gravity,and is temporarily fixed so that the center of the solder ball 400substantially coincides with the center line CL on the V-shaped notchedsection 41 and does not move in the virtual right angle axis directionbetween the two pads. As a result, the solder ball 400 will no longermove even if subjected to some kind of stress in the virtual right angleaxis direction (direction A or direction B shown in FIG. 8) due to thesubsequent injection of nitrogen gas, etc., or vibration when theoptical apparatus 200 moves, for example.

As the width of the section parallel to the center line CL in theV-shaped notched section 41, if, for example, the width of a lead wiringpad 40 is 148 mm and the diameter of the solder ball is 120 mm, theangle of the V-shaped notched section 41 should be determined so as tocontact the lead wiring pad 40 at a point where the width is ⅓ (approx.49 mm) the width of a lead wiring pad 40.

In this embodiment, a V-shaped notched section 41 is formed peripheralto the center line CL of a lead wiring pad 40, but a different shape mayalso be formed as long as it is a shape that enables a solder ball 400to be dropped into it under the force of gravity. For example, arectangular or rhomboidal notched section may be provided in thevicinity of the center of a lead wiring pad 40.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a V-shaped notched section 41 in a lead wiring pad 40, inthe same way as in the other embodiments described above, the center ofa solder ball 400 substantially coincides with the center line CL of thelead wiring pad 40, and is temporarily fixed so that it does not move inthe virtual right angle axis direction between the two pads, as a resultof which the solder ball 400 will no longer move in the right angle axisdirection even if subjected to some kind of stress in the virtual rightangle axis direction due to subsequent injection of an inert gas ormovement of the optical apparatus 200, for example, and moreover, thefact that the shape of the V-shaped notched section 41 is a V also makesit difficult for the solder ball 400 to move toward the apex of the V,and so makes the solder ball 400 all the more stable, thereby enablingthe good solder connection state shown in FIG. 5 to be achieved.

FIG. 9 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 4 of thepresent invention. The only difference between this embodiment andEmbodiment 1 is that the shape of the lead wiring pads 50 is different.Otherwise the configuration is the same as that of the integrated leadsuspension according to Embodiment 1 shown in FIGS. 1 through 6.

With a lead wiring pad 50 of this embodiment, the same kind of pad as aconventional lead wiring pad shown in FIG. 15 is first formed, in thesame way as in Embodiment 1, and then bending is further performed onthat pad. The method of forming a pad of the same kind as a conventionallead wiring pad is the same as in Embodiment 1. In this embodiment,following this, the lead wiring pads 50 are further deformed using a dieor the like (not shown), and the bent section 51 shown in FIG. 9 isformed in each lead wiring pad 50.

As a result, a bent section (recessed section) 51 is formed along thecenter line CL in each lead wiring pad 50 of this embodiment, and oneither side of the bent section 51 are formed an inclined section(raised section) 52 and inclined section (raised section) 53 slopingtoward the bent section 51.

As the bent section 51 is linear in shape and is formed so as tocoincide with the center line CL, and inclined section 52 and inclinedsection 53 on either side of the bent section 51 slope toward the bentsection 51, a solder ball 400 is dropped into the bent section 51—thatis, between inclined section 52 and inclined section 53—under the forceof gravity, and is temporarily fixed so that the center of the solderball 400 substantially coincides with the center line CL on the bentsection 51 and does not move in the virtual right angle axis directionbetween the two pads. As a result, the solder ball 400 will no longermove even if subjected to some kind of stress in the virtual right angleaxis direction (direction A or direction B shown in FIG. 9) due to thesubsequent injection of nitrogen gas, etc., or vibration when theoptical apparatus 200 moves, for example.

In this embodiment, a single bent section 51 is formed coincident withthe center line CL of a lead wiring pad 50, but a plurality of bentsections may also be formed centered on the center line CL, as long astheir shape enables a solder ball 400 to be 15 dropped into them underthe force of gravity.

Also, the bent section 51 is not limited to the case where a bend ismade in a straight line as shown in FIG. 9, and the bent section 51 mayalso be configured, for example, so as to sink gently on a curvedsurface.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a bent section 51 in a lead wiring-pad 50, in the same wayas in the other embodiments described above, the center of a solder ball400 substantially coincides with the center line CL of the lead wiringpad 50, and is temporarily fixed so that it does not move in the virtualright angle axis direction between the two pads, as a result of whichthe solder ball 400 will no longer move in the right angle axisdirection even if subjected to some kind of stress in the virtual rightangle axis direction due to subsequent injection of an inert gas ormovement of the optical apparatus 200, for example, thereby enabling thegood solder connection state shown in FIG. 5 to be achieved.

FIG. 10 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 5 of thepresent invention. The only difference between this embodiment andEmbodiment 4 is that the shape of the lead wiring pads 60 is different.Otherwise the configuration is the same as that of the integrated leadsuspension according to Embodiment 4 shown in FIG. 9.

With a lead wiring pad 60 of this embodiment, the same kind of flat padas a conventional lead wiring pad shown in FIG. 15 is first formed, inthe same way as in Embodiment 4, and then bending is performed on itssurface, but in this embodiment both sides of the pad have a bentsection. The method of forming a pad of the same kind as a conventionallead wiring pad is the same as in Embodiment 1 or Embodiment 4. In thisembodiment, following this, the lead wiring pads 60 are further deformedusing a die or the like (not shown), and a bent section 62 and bentsection 63 are bent upward from each lead wiring pad 60 as shown in FIG.10. As a result, a bent section (raised section) 62 and bent section(raised section) 63, bent upward and parallel to the center line CL, areformed on either side of the flat section 61 (recessed section) on eachlead wiring pad 60 of this embodiment.

As bent section 62 and bent section 63 are rectangular and formed sothat the long sides are parallel to the center line CL, and are bentupward, a solder ball 400 is dropped onto the flat section 61—that is,between bent section 62 and bent section 63—under the force of gravity,and is temporarily fixed so that the center of the solder ball 400substantially coincides with the center line CL on the flat section 61and does not move in the virtual right angle axis direction between thetwo pads. As a result, the solder ball 400 will no longer move even ifsubjected to some kind of stress in the virtual right angle axisdirection (direction A or direction B shown in FIG. 9) due to thesubsequent injection of nitrogen gas, etc., or vibration when theoptical apparatus 200 moves, for example.

In this embodiment, a bent section 62 and bent section 63 are formedparallel to the center line CL on a lead wiring pad 60, but a bentsection 62 and bent section 63 may also be formed at a sloping anglecentered on the center line CL, as long as their shape enables a solderball 400 to be dropped between them under the force of gravity.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a bent section 62 and bent section 63 on a lead wiring pad60, in the same way as in the other embodiments described above, thecenter of a solder ball 400 substantially coincides with the center lineCL of the lead wiring pad 60, and is temporarily fixed so that it doesnot move in the virtual right angle axis direction between the two pads,as a result of which the solder ball 400 will no longer move in theright angle axis direction even if subjected to some kind of stress inthe virtual right angle axis direction due to subsequent injection of aninert gas or movement of the optical apparatus 200, for example, therebyenabling the good solder connection state shown in FIG. 5 to beachieved.

FIG. 11 is an oblique drawing showing an enlarged view of the main partsin an integrated lead suspension according to Embodiment 6 of thepresent invention. The only difference between this embodiment andEmbodiment 1 is that the shape of the lead wiring pads 70 is different.Otherwise the configuration is the same as that of the integrated leadsuspension according to Embodiment 1 shown in FIGS. 1-6.

With a lead wiring pad 70 of this embodiment, the same kind of pad as aconventional lead wiring pad shown in FIG. 15 is first formed, in thesame way as in Embodiment 1, and then press working is further performedon that pad. The method of forming a pad of the same kind as aconventional lead wiring pad is the same as in Embodiment 1. In thisembodiment, following this, the lead wiring pads 70 are furtherpress-deformed using a die or the like (not shown), and the sunkensection (recessed section) 71 shown in FIG. 11 is formed in each leadwiring pad 70. As a result, a sunken section 71 is formed along thecenter line CL in each lead wiring pad 70 of this embodiment, and oneither side of the sunken section 71 are formed a raised section 72 anda raised section 73.

The sunken section 71 in this embodiment is of a similar U-shape to thatin Embodiment 2 and is formed so that its center coincides with thecenter line CL, and there is a difference in level between the sunkensection 71, and raised section 72 and raised section 73 on either sideof the sunken section 71, in the same way as in Embodiment 1, so that asolder ball 400 is dropped into the sunken section 71—that is, betweenraised section 72 and raised section 73—under the force of gravity, andis temporarily fixed so that the center of the solder ball 400substantially coincides with the center line CL on the sunken section 71and does not move in the virtual right angle axis direction between thetwo pads. As a result, the solder ball 400 will no longer move even ifsubjected to some kind of stress in the virtual right angle axisdirection (direction A or direction B shown in FIG. 11) due to thesubsequent injection of nitrogen gas, etc., or vibration when theoptical apparatus 200 moves, for example. The dimensions of the U-shapecan be set in the same way as in Embodiment 2.

In this embodiment, a U-shaped sunken section 71 is formed on a leadwiring pad 70 centered on the center line CL with the opening sidefacing downward, as in Embodiment 2, but a sunken section of a differentshape centered on the center line CL may also be formed as long as itsshape enables a solder ball 400 to be dropped into it under the force ofgravity.

The difference in level formed by the sunken section 71 need not be asharply-defined difference in level as shown in FIG. 11, but, forexample, may be configured so that the sunken section 71 sinks gentlybelow raised section 72 and raised section 73 on a curved surface, ormay be configured so that the sunken section 71 sinks gently belowraised section 72 and raised section 73 on an inclined surface.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a sunken section 71 in a lead wiring pad 70, in the sameway as in the other embodiments described above, the center of a solderball 400 substantially coincides with the center line CL of the leadwiring pad 70, and is temporarily fixed so that it does not move in thevirtual right angle axis direction between the two pads, as a result ofwhich the solder ball 400 will no longer move in the right angle axisdirection even if subjected to some kind of stress in the virtual rightangle axis direction due to subsequent injection of an inert gas ormovement of the optical apparatus 200, for example, thereby enabling thegood solder connection state shown in FIG. 5 to be achieved.

FIG. 12 comprises oblique drawings showing enlarged views of the mainparts in an integrated lead suspension according to Embodiment 7 of thepresent invention. FIG. 12(A) is a drawing showing pads of the same kindas conventional lead wiring pads during the process of manufacture, andFIG. 12(B) is a drawing showing lead wiring pads of this embodiment. Theonly difference between this embodiment and Embodiment 1 is that theshape of the lead wiring pads 80 a shown in FIG. 12(B) is different.However, in order to form lead wiring pads 80 a, use of an additive typemanufacturing method is necessary, and therefore the manufacturingmethod for an integrated lead suspension of this embodiment is limitedto an additive type. Otherwise the configuration is the same as that ofthe integrated lead suspension according to Embodiment 1 shown in FIGS.1 through 6.

With a lead wiring pad 80 a of this embodiment, a lead wiring pad 80 ofthe same kind as a conventional lead wiring pad shown in FIG. 12(A) isfirst formed, in the same way as in Embodiment 1, and then copperplating is added to the areas on both sides excluding the vicinity ofthe center line CL on the surface of this pad 80. The method of forminga lead wiring pad 80 of the same kind as a conventional lead wiring padis the same as in Embodiment 1.

A recessed groove section (recessed section) 81, and a raised section 82and raised section 83, are formed by coating areas other than thevicinity of the center line CL (necessary areas) on the lead wiring pad80 with a resist, performing Cu (copper) plating, and then removing theresist.

Due to the fact that a recessed groove section 81 of this embodiment isformed so that its center coincides with the center line CL as inEmbodiment 1, and that there is a difference in level between therecessed groove section 81, and raised section 82 and raised section 83on either side of the recessed groove section 81, as in Embodiment 1, asolder ball 400 is dropped into the recessed groove section 81—that is,between raised section 82 and raised section 83—under the force ofgravity, and is temporarily fixed so that the center of the solder ball400 substantially coincides with the center line CL on the recessedgroove section 81 and does not move in the virtual right angle axisdirection between the two pads. As a result, the solder ball 400 will nolonger move even if subjected to some kind of stress in the virtualright angle axis direction (direction A or direction B shown in FIG.12(B)) due to the subsequent injection of nitrogen gas, etc., orvibration when the optical apparatus 200 moves, for example. Thedimensions of the recessed groove section can be set in the same way asin Embodiment 1.

In this embodiment, a recessed groove section 81 of the same kind ofshape as in Embodiment 1 is formed in a lead wiring pad 80 a, centeredon the center line CL, but a recessed section of a different shape mayalso be formed centered on the center line CL, as long as its shapeenables a solder ball 400 to be dropped into it under the force ofgravity.

The difference in level formed by the recessed groove section 81 neednot be a sharply-defined difference in level as shown in FIG. 12, but,for example, may be configured so that the recessed groove section 81sinks gently below raised section 82 and raised section 83 on a curvedsurface, or may be configured so that the recessed groove section 81sinks gently below raised section 82 and raised section 83 on aninclined surface.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a recessed groove section 81 in a lead wiring pad 80 a, inthe same way as in the other embodiments described above, the center ofa solder ball 400 substantially coincides with the center line CL of thelead wiring pad 80 a, and is temporarily fixed so that it does not movein the virtual right angle axis direction between the two pads, as aresult of which the solder ball 400 will no longer move in the rightangle axis direction even if subjected to some kind of stress in thevirtual right angle axis direction due to subsequent injection of aninert gas or movement of the optical apparatus 200, for example, therebyenabling the good solder connection state shown in FIG. 5 to beachieved.

FIG. 13 comprises oblique drawings showing enlarged views of the mainparts in an integrated lead suspension according to Embodiment 8 of thepresent invention. FIG. 13(A) is a drawing showing pad base sectionsformed by etching, etc., on a polyimide layer, which is insulatingpolymeric material, during the process of manufacture, and FIG. 13(B) isa drawing showing lead wiring pads of this embodiment.

The only differences between this embodiment and Embodiment 1 are thatthe pad base sections 95 shown in FIG. 13(A) are formed on apolyimidelayer 17, and that the shape of the lead wiring pads 90 shown in FIG.13(B) is different. However, in order to form lead wiring pads 90 on thepad base sections 95, use of an additive type manufacturing method isnecessary, and therefore the manufacturing method for an integrated leadsuspension of this embodiment is limited to an additive type. Otherwisethe configuration is the same as that of the integrated lead suspensionaccording to Embodiment 1 shown in FIGS. 1 through 6.

Pad base sections 95 of this embodiment are formed, for example, by aprocess in which the polyimide layer 17 is etched when an integratedlead suspension is manufactured. At this time, following normal etchingto obtain the external shape of pad base sections 95 from the polyimidelayer 17, half-etching is performed with resist applied in a shapeexcluding U-shaped underlying recessed section 96 parts with the openingside facing downward so that the center line CL and center axiscoincide. If the polyimide layer 17 is a photosensitive polyimide layer,pad base sections 95 are formed by a process in which the polyimidelayer 17 is exposed and developed when an integrated lead suspension ismanufactured, and the U-shaped underlying recessed sections 96, baseraised sections 97, and base raised sections 98 shown in FIG. 13(A) areformed by performing exposure and development after applying resist in ashape excluding the U-shaped underlying recessed section 96 parts.

Next, as with a conventional additive type manufacturing method, leads10, lead wiring pads 90, and so forth, are formed on the polyimide layer17 by copper plating. At this time, raised sections 92 and raisedsections 93 forming the two sides of each lead wiring pad 90 formed bycopper plating are formed to the same height as in Embodiment 1 on thebase raised sections 97 and base raised sections 98 of the polyimidelayer 17. However, a greater degree of depression occurs on eachU-shaped underlying recessed section 96 of the polyimide layer 17 thanon the areas on either side, as in Embodiment 6, and a U-shaped sunkensection (recessed section) 91 is formed in each lead wiring pad 90formed by copper plating. The dimensions of the U-shape can be set inthe same way as in Embodiment 2.

Due to the fact that a U-shaped sunken section 91 of this embodiment isformed so as to be of a similar U-shape to that in Embodiment 6 and sothat its center coincides with the center line CL, and that there is adifference in level between the sunken section 91, and raised section 92and raised section 93 on either side of the sunken section 91, as inEmbodiment 1, a solder ball 400 is dropped into the sunken section91—that is, between raised section 92 and raised section 93—under theforce of gravity, and is temporarily fixed so that the center of thesolder ball 400 substantially coincides with the center line CL on thesunken section 91 and does not move in the virtual right angle axisdirection between the two pads. As a result, the solder ball 400 will nolonger move even if subjected to some kind of stress in the virtualright angle axis direction (direction A or direction B shown in FIG.13(B)) due to the subsequent injection of nitrogen gas, etc., orvibration when the optical apparatus 200 moves, for example.

In this embodiment, a sunken section 91 of the same kind of U-shape asin Embodiment 6 is formed in a lead wiring pad 90, centered on thecenter line CL, but a sunken section of a different shape may also beformed centered on the center line CL, as long as its shape enables asolder ball 400 to be dropped into it under the force of gravity.

The difference in level formed by the sunken section 91 need not be asharply-defined difference in level as shown in FIG. 13, but, forexample, may be configured so that the sunken section 91 sinks gentlybelow raised section 92 and raised section 93 on a curved surface, ormay be configured so that the sunken section 91 sinks gently belowraised section 92 and raised section 93 on an inclined surface.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a sunken section 91 in a lead wiring pad 90, in the sameway as in the other embodiments described above, the center of a solderball 400 substantially coincides with the center line CL of the leadwiring pad 90, and is temporarily fixed so that it does not move in thevirtual right angle axis direction between the two pads, as a result ofwhich the solder ball 400 will no longer move in the right angle axisdirection even if subjected to some kind of stress in the virtual rightangle axis direction due to subsequent injection of an inert gas ormovement of the optical apparatus 200, for example, thereby enabling thegood solder connection state shown in FIG. 5 to be achieved.

FIG. 14 comprises oblique drawings showing enlarged views of the mainparts in an integrated lead suspension according to Embodiment 9 of thepresent invention. FIG. 14(A) is a drawing showing pad base sectionsformed by etching, etc., on a polyimide layer, which is insulatingpolymeric material, during the process of manufacture, and FIG. 14(B) isa drawing showing lead wiring pads of this embodiment.

The only difference between this embodiment and Embodiment 8 is that theshape of the pad base sections 105 shown in FIG. 14(A) and the shape ofthe lead wiring pads 100 shown in FIG. 14(B) are different, the factthat the manufacturing method for an integrated lead suspension of thisembodiment is limited to an additive type being a point of similaritywith Embodiment 8. Otherwise the configuration is the same as that ofthe integrated lead suspension according to Embodiment 8 shown in FIG.13.

Pad base sections 105 of this embodiment are formed, for example, by aprocess in which the polyimide layer 17 is etched when an integratedlead suspension is manufactured. At this time, following normal etchingto obtain the external shape of pad base sections 105 from the polyimidelayer. 17, half-etching is performed with resist applied in a shapeexcluding V-shaped underlying recessed section 106 parts with theopening side facing downward so that the center line CL and center axiscoincide. If the polyimide layer 17 is a photosensitive polyimide layer,pad base sections 105 are formed by a process in which the polyimidelayer 17 is exposed and developed when an integrated lead suspension ismanufactured, and the V-shaped underlying recessed sections 106, baseraised sections 107, and base raised sections 108 shown in FIG. 14(A)are formed by performing exposure and development after applying resistin a shape excluding the V-shaped underlying recessed section 106 parts.

Next, as with a conventional additive type manufacturing method, leads10, lead wiring pads 100, and so forth, are formed on the polyimidelayer 17 by copper plating. At this time, raised sections 102 and raisedsections 103 forming the two sides of each lead wiring pad 100 formed bycopper plating are formed to the same height as in Embodiment 1 on thebase raised sections 107 and base raised sections 108 of the polyimidelayer 17. However, a greater degree of depression occurs on eachV-shaped underlying recessed section 106 of the polyimide layer 17 thanon the areas on either side, and a V-shaped sunken section (recessedsection) 101 is formed in each lead wiring pad 100 formed by copperplating. The dimensions of the V-shape can be set in the same way as inEmbodiment 3.

Due to the fact that a V-shaped sunken section 101 of this embodiment isformed so that the center of the V coincides with the center line CL,and that there is a difference in level between the sunken section 101,and raised section 102 and raised section 103 on either side of thesunken section 101, as in Embodiment 1, a solder ball 400 is droppedinto the sunken section 101—that is, between raised section 102 andraised section 103—under the force of gravity, and is temporarily fixedso that the center of the solder ball 400 substantially coincides withthe center line CL on the sunken section 101 and does not move in thevirtual right angle axis direction between the two pads. As a result,the solder ball 400 will no longer move even if subjected to some kindof stress in the virtual right angle axis direction (direction A ordirection B shown in FIG. 14(B)) due to the subsequent injection ofnitrogen gas, etc., or vibration when the optical apparatus 200 moves,for example.

In this embodiment, a V-shaped sunken section 101 is formed in a leadwiring pad 100, centered on the center line CL, but a sunken section ofa different shape may also be formed centered on the center line CL, aslong as its shape enables a solder ball 400 to be dropped into it underthe force of gravity.

The difference in level formed by the sunken section 101 need not be asharply-defined difference in level as shown in FIG. 14, but, forexample, may be configured so that the sunken section 101 sinks gentlybelow raised section 102 and raised section 103 on a curved surface, ormay be configured so that the sunken section 101 sinks gently belowraised section 102 and raised section 103 on an inclined surface.

Thus, with an integrated lead suspension of this embodiment, through theprovision of a sunken section 101 in a lead wiring pad 100, in the sameway as in the other embodiments described above, the center of a solderball 400 substantially coincides with the center line CL of the leadwiring pad 100, and is temporarily fixed so that it does not move in thevirtual right angle axis direction between the two pads, as a result ofwhich the solder ball 400 will no longer move in the right angle axisdirection even if subjected to some kind of stress in the virtual rightangle axis direction due to subsequent injection of an inert gas ormovement of the optical apparatus 200, for example, and moreover, thefact that the shape of the sunken section 101 is a V also makes itdifficult for the solder ball 400 to move toward the apex of the V, andso makes the solder ball 400 all the more stable, thereby enabling thegood solder connection state shown in FIG. 5 to be achieved.

In the above-described embodiments, when a bonding pad and lead wiringpad are connected by means of a solder ball, the virtual angle formedbetween that bonding pad and lead wiring pad is assumed to be a rightangle, but this angle may be changed to any angle as long as it is anangle that enables a solder ball 400 to be caught.

Similarly, in the above-described embodiments, a lead wiring pad andbonding pad fixes a flexure as to both be at an angle of 45 degreesabove the horizontal, but this angle also may be changed to any angle aslong as it is an angle that enables a solder ball 400 to be caught.

Also, in the above-described embodiments, cases of a groove, a V-shape,and a U-shape are mentioned with regard to the shape of recessedsections, but the advantages of the present invention can also beobtained with recessed sections of any shape, including circular, oval,rectangular, or rhomboidal.

As described above, with a integrated lead suspension of the presentinvention, through the provision of a recessed section in a lead wiringpad, the center of a solder ball substantially coincides with the centerline of the lead wiring pad, and is temporarily fixed so that it doesnot move in a virtual right angle axis direction between the two pads,as a result of which the solder ball no longer moves in a right angleaxis direction even if subjected to some kind of stress in the virtualright angle axis direction due to subsequent injection of an inert gas,movement of the optical apparatus, or the like, thereby enabling a goodsolder connection state to be achieved.

Also, with the present invention in which a recessed section in a leadwiring pad is made V-shaped, in addition to the above-describedadvantage, the fact that the shape of the recessed section is a V alsomakes it difficult for a solder ball to move toward the apex of the V,and so makes the solder ball more stable, thereby enabling a good solderconnection state to be achieved.

1. An integrated lead suspension, comprising: a lead wiring pad providedon a flexure section of the suspension, a bonding pad provided on aslider of a head gimbal section of the suspension, and a solder ballthat is placed between the lead wiring pad and the bonding pad, so thatthe solder ball is melted to solder the lead wiring pad and the bondingpad together; and the suspension comprises a bent section into which thesolder ball is dropped from the surface of the lead wiring pad, usinggravitational force, adjacent to the center line of the surface of thelead wiring pad; and wherein in the bent section, an inclined surface isformed between a portion into which the solder ball is dropped andportions on both sides of said portion, wherein the entire surface ofthe pad is inclined.